On 30 November 1941 a sunfish Mola mola (L.) was found on the beach near Schoorl (Province of Noord-Holland). The fish was parasitized by a specimen of Pennella filosa (L.) (Crustacea, Copepoda) on which a specimen of Conchoderma virgatum (Crustacea: Cirripedia) had attached itself. This is the first and so far only record of these two crustaceans for The Netherlands.Another species of the genus Pennella, P. crassicornis Steenstrup & Lütken, had been previously recorded from the Dutch coast (on Balaenoptera acutorostrata Lacépède); this record is also discussed here.